Dust collector for an angle grinder

ABSTRACT

A dust collector for an angle grinder, comprising a collector body for covering a circular grinding wheel, and a sealing element extending along an outer periphery (U) of the collector body for at least partially sealing the collector body against a surface to be machined by means of the grinding wheel, and comprising a suction connection, by way of which material removed from the surface can be suction out of the collector body. In an axial direction with respect to the axis of rotation (R) of the grinding wheel, the sealing element is spring-mounted in the collector body by means of at least one spring element.

The present invention relates to a dust collector for an angle grinder,comprising a collector body for covering a circular grinding wheel, anda sealing element extending along an outer periphery of the collectorbody for at least partially sealing the collector body against a surfaceto be machined by means of the grinding wheel. The dust collector for anangle grinder has a suction connection, by way of which material removedfrom the surface can be suctioned out of the collector body. The sealingelement can be, for example, a brush curtain, lamellae, or the like. Inaddition, it is also possible that the sealing element involves a singlesolitary elastic element or also multiple individual elastic elements.The elastic element can be a foam, an elastomer (for example, rubber,natural rubber, etc.), or the like.

Dust collectors for angle grinders of the type mentioned at the outsetare known in principle from the prior art. They are used to avoidpropagation of dust during grinding work, in order to protect the healthof a user of the angle grinder. Equipping the collector body with asealing element, for example, a peripheral brush curtain or withmultiple brushes, such that the collector body terminates at the surfaceof the workpiece to be machined, is known. If the angle grinder ispressed at a slight angle against the surface of the workpiece to bemachined, the sealing element can thus seal a gap possibly arisingbetween collector body and surface of the workpiece to be machined in acompensating manner.

It is the object of the present invention to provide a dust collectorfor an angle grinder which offers improved usage options.

The object is achieved in that, in an axial direction with respect tothe axis of rotation of the grinding wheel, the sealing element isspring-mounted in the collector body by means of at least one springelement.

The invention includes the finding that in particular during overheadoperation of an angle grinder, a collector body comprising brush curtainrigidly fastened thereon according to the prior art is drawn downward bygravity and a suction hose possibly connected to the suction connection.A gap can thus disadvantageously arise between brush curtain and surfaceto be machined. The brush curtain is always pressed toward the surfaceto be machined by the spring-mounted brush curtain in the collector bodyaccording to the invention, whereby a gap is avoided or at leastsubstantially reduced.

In this respect, the invention also includes the finding that a wornbrush curtain can typically have a high stiffness in relation to theaxial direction, and therefore disadvantageously a large amount of forcehas to be applied to move the grinding wheel toward the surface of theworkpiece to be machined against the stiffness of the warned brushcurtain. This is the case because the brush curtain is rigidly fastenedto the collector body in dust collectors for angle grinders of the priorart, as already mentioned at the outset.

In addition, the present invention includes the finding that a grindingwheel which is already strongly worn, in particular a diamond cup wheel,is used in conjunction with a new dust collector for an angle grinderand the user disadvantageously has to press the grinding wheel, whichhas already become flat, toward the surface of the workpiece to bemachined against the relatively high stiffness of the still stiff brushcurtain of the new dust collector for an angle grinder. A worn grindingwheel frequently has a lesser height in this case, i.e., a less concaveshape than a new or unworn grinding wheel.

In the dust collector for a grinding wheel according to the invention,the spring element assumes the axial movement of the sealing elementwith respect to the collector body. Possible radial displacements canstill be compensated for by the sealing element itself. In the scope ofthe invention, a spring element is to be understood as a preferablydiscrete spring element and not merely a possible spring action oryielding nature of the brush curtain in the axial direction.

In addition, the invention includes the finding that dust collectors forangle grinders of the prior art cannot be refined to achieve the springaction according to the invention such that a spring element is providedbetween collector body and angle grinder housing, for example. This hasthe disadvantage during overhead work that the intrinsic weight of asuction hose connected to the suction connection would compress such aspring in an undesired manner.

In a particularly preferred embodiment, the collector body is designedto cover a predominant part of the grinding wheel. The dust collectorfor an angle grinder can have a collector segment displaceable along thecollector body in the peripheral direction of the collector body, whichis provided to cover and expose a remaining part of the grinding wheelgradually as needed. This enables grinding operation close to the wallby means of the remaining part of the grinding wheel, which is notcovered by the collector body. In an axial direction with respect to theaxis of rotation of the grinding wheel, a sealing element is preferablyalso spring-mounted by at least one spring element in the collectorsegment.

It has proven to be advantageous if the spring element has a preferablyflatly formed base web. The spring element can be fastened on thecollector body and/or on the collector segment via the base web.Fastening preferably takes place by means of a pin, a screw, and/or arivet. In addition, it can also be provided that the spring element isfastened directly in the collector body by means of a spring clip via anundercut. The spring clip can also be referred to as a clip, andtherefore the spring element is clipped into the collector body.Furthermore, the spring element can also be injection molded directlyinto the collector body or into the collector housing, respectively. Atleast one hole is preferably provided in the base web, in which a pin, ascrew, or a rivet can engage.

Alternatively, it could also be provided that the spring element isfastened on the first and/or second holding rail for the sealingelement.

The spring element is or the spring elements are preferably arrangedinside a volume defined by the collector body or collector segment. Thecollector body and/or the collector segment preferably has a housingsection, the curvature of which corresponds to the curvature of thegrinding wheel. The spring element is preferably arranged in theimmediate vicinity of this section. The spring element is preferablyarranged as far as possible from an axis of rotation of the grindingwheel inside the collector body volume or the collector segment volume.

It has proven to be advantageous if the spring element has at least onespring rocker arm protruding from the base web. The spring element ispreferably attached such that the orientation of the protruding springrocker arm preferably approximately corresponds to the outercircumference of the collector body.

According to a further embodiment, it could also be provided that thespring element is also radially arranged.

Alternatively, it can also be provided that the spring element has twospring rocker arms protruding from the base web. In this way, a higherlevel of stability of the spring element in an installed state and alsoan enhanced spring force can be achieved.

When the spring element is installed, the spring rocker arms form atangent to the circular grinding wheel or to the oval body of the dustcollector.

In one particularly preferred embodiment, the spring element has atleast one holding bracket, which is designed to prevent the brushcurtain from falling axially out of the collector body and/or thecollector segment.

The holding bracket can protrude in the axial direction from the baseweb. An axial stop for a holding rail of the brush curtain is preferablyformed at its other end, i.e., the end facing away from the base web.

The holding bracket can preferably be deflected in the radial direction,in relation to the axis of rotation of the grinding wheel, for thepurpose of replacing the brush curtain. Furthermore, the axial stop canadvantageously be formed as a stop web, which preferably extendsparallel to the base web. The axial stop formed as a stop webadvantageously has a recess, and therefore a contact surface betweenstop web and brush curtain or holding rail of the brush curtain isreduced. The recess preferably causes a material savings and a smallerengagement surface for dust. Moreover, a friction surface with respectto the brush curtain is reduced, and therefore it can be movedparticularly easily in the axial direction.

Alternatively to the holding bracket being able to protrude in the axialdirection from the base web, the holding bracket can be designed as aclamping sleeve, which is arranged on a side of a respective springrocker arm facing away from the base web. The clamping sleeve ispreferably designed for clamping a holding rail of the brush curtain. Inother words, the clamping sleeve which holds the brush curtain is itselfspring-mounted.

It has proven to be advantageous if the spring element is formed in onepiece, preferably from spring steel. The spring element particularlypreferably has a spring stiffness in the axial direction which is lessthan a stiffness of the brushes comprised by the brush curtain.Alternatively, the spring element can also be embodied in multiplepieces.

A plurality of spring elements is particularly preferably provided alongthe circumference of the collector body and/or the collector segment. Ithas proven to be advantageous if a dust collector for an angle grinder,which has a collector body and a collector segment, is equipped withfive spring elements, preferably spaced apart uniformly from oneanother.

In a further preferred embodiment, the collector body has a centralopening, through which a drive spindle, on which the circular grindingwheel is to be attached for grinding operation, can protrude through thecentral opening. A groove is preferably formed at the central opening,and therefore the collector body can be fastened interlocked and thusfixed on the frame on an angle grinder.

The object is also achieved by an angle grinder comprising a dustcollector for an angle grinder of the above-described type, wherein thecollector body is arranged or can be arranged fixed on the frame on theangle grinder.

Further advantages result from the following description of the figures.Various exemplary embodiments of the present invention are illustratedin the figures. The figures, the description, and the claims containnumerous features in combination. A person skilled in the art willexpediently also consider the features individually and combine them toform reasonable further combinations.

In the figures, identical and equivalent components are identified byidentical reference signs. In the figures:

FIG. 1 shows a schematic bottom view of a dust collector for an anglegrinder according to the invention comprising a spring element accordingto a first alternative;

FIG. 2 shows a sectional illustration of the exemplary embodiment fromFIG. 1;

FIG. 3 shows a spring element according to a second alternative;

FIG. 4 shows the spring element from FIG. 3 in a side view.

EXEMPLARY EMBODIMENTS:

A dust collector 100 for an angle grinder according to the invention isshown in a bottom view in FIG. 1. The dust collector 100 for the anglegrinder has a collector body 10 for covering a circular grinding wheel(not shown here). An axis of rotation R of the grinding wheel isindicated by a dot-dash line. The dust collector 100 for the anglegrinder also has a collector segment 20, which is displaceable along thecollector body 10 along a peripheral direction U of the collector body10.

The collector body 10 is designed to cover a predominant part of thegrinding wheel, wherein the displaceable collector segment 20 isprovided for covering and exposing a remaining part of the grindingwheel.

Both the collector body 10 and also the displaceable collector segment20 have a sealing element 30 in the form of a brush curtain. Since thedust collector 100 for the angle grinder of FIG. 1 has both a collectorbody 10 and also a collector segment 20, the brush curtain 20 is formedin two pieces or two brush curtains are provided. The brush curtains 30are used to seal the collector body 10 and the collector segment 20against a surface to be machined, which is not shown here. Materialremoved from the surface in the course of the machining can be suctionedout via a suction connection 40 provided on the collector body 10.

According to the invention, in an axial direction with respect to theaxis of rotation R of the grinding wheel, the brush curtain 30 isspring-mounted in the collector body 10 and the collector segment bymeans of at least one spring element 50. The spring element 50 is shownisolated on the left side of FIG. 1.

The spring element 50 has a flatly formed base web 51, via which thespring element 50 is fastened on the collector body or collector segment20. In the exemplary embodiment shown in FIG. 1, the spring element 50is fastened (for example, hot caulked) via a pin 52 (cf. FIG. 2),wherein the pin engages in a hole 52′.

The spring element 50 has two spring rocker arms 53 protruding from thebase web 51 in opposing orientations. The spring rocker arms 53 exert aspring action on a holding rail 31 of the brush curtain 30. The springrocker arms 53 are oriented in the direction of the outer periphery U ofthe collector body 10 when the spring element 50 is installed.

The spring element 50 has a holding bracket 55, which is designed toprevent the brush curtain 30 from falling axially out of the collectorbody 10 or the collector segment 20, respectively. In the exemplaryembodiment shown in FIG. 1, the holding bracket 55 protrudes in theaxial direction from the base web 51 and has a stop for the holding rail31 of the brush curtain at its other end. The axial stop is formed inthe present case as a stop web 57, which extends parallel to the baseweb 51 and has a recess 59.

The holding bracket 55 can be deflected in the radial direction,indicated by the double arrow, for the purpose of replacing the brushcurtain. The brush curtain 30 can thus advantageously be replacedwithout a tool being required.

As is apparent from FIG. 1, a functional integration is implemented bythe spring element 50, namely, on the one hand, the spring action in theaxial direction according to the invention, on the other hand, the brushcurtain is prevented from falling out of the collector body 10 or thecollector segment 20, respectively.

As can be inferred from FIG. 1, the collector body 10 has a centralopening 11, through which a drive spindle (not shown here), on which thecircular grinding wheel is to be attached, can protrude through thecentral opening 11. A groove 12 is formed at the central opening, andtherefore the collector body 10 can be fastened interlocked and thusfixed on the frame on an angle grinder.

FIG. 2 shows a sectional illustration of the exemplary embodiment of thedust collector 100 for an angle grinder from FIG. 1.

It can be seen well that the spring elements 50 arranged inside a volumeof the collector body 10 at the outer edge of the collector body 10exert a spring action on the holding rail 31 of the brush curtain 30 byway of the respective spring rocker arms 53 thereof. At the same time,the respective stop webs 57 form an axial stop for the holding rail 31,and therefore it is held securely inside the collector body 10.

FIG. 3 shows a spring element 50′ according to a second alternative. Theholding bracket 55 is designed as a clamping sleeve, which is arrangedon a side of a respective spring rocker arm 53 facing away from the baseweb 51. The holding bracket 55 designed as a clamping sleeve is used toclamp the holding rail 31 of the brush curtain 30 (cf. FIG. 4).

The spring element 50 shown in FIG. 3 is particularly suitable forcomparatively narrow holding rails, with respect to the radialdirection. Possible manufacturing tolerances of the holding rail can becompensated for well because the holding brackets 55 are designed asclamping sleeves.

Finally, FIG. 4 shows the spring element of FIG. 3 in a side view,wherein a brush curtain 30 with holding rail 31, which is in the process(indicated by the arrow) of being clamped in the holding bracket 55designed as a clamping sleeve, is illustrated above the holding bracket55 designed as a clamping sleeve.

Two holes 52, 52′ are provided on the base web 51 of the spring element50 of FIG. 3, in order to fasten the element 50 in the same manner as inFIGS. 1 and 2 by means of two pins 52 on the collector body 10 or on thecollector segment 20.

1. A dust collector for an angle grinder, comprising a collector body(10) for covering a circular grinding wheel, and a sealing elementextending along an outer periphery of the collector body for at leastpartially sealing the collector body against a surface to be machined bythe circular grinding wheel, and comprising a suction connection, by wayof which material removed from the surface can be suctioned out of thecollector body, wherein, in an axial direction with respect to an axisof rotation (R) of the grinding wheel, the sealing element isspring-mounted in the collector body by at least one spring element. 2.The dust collector for an angle grinder as claimed in claim 1, whereinthe collector body is designed to cover a predominant part of thegrinding wheel and the dust collector has a collector segmentdisplaceable along the collector body in a peripheral direction (U) ofthe collector body, the collector segment arranged for graduallycovering and exposing of a part of the grinding wheel as needed, andwherein in the axial direction with respect to the axis of rotation (R)of the grinding wheel, the sealing element is also spring-mounted in thecollector segment by the at least one spring element.
 3. The dustcollector for an angle grinder as claimed in claim 1, wherein the springelement has a base web, via which the at least one spring element isfastened on the collector body.
 4. The dust collector for an anglegrinder as claimed in claim 3, wherein the at least one spring elementhas at least one spring rocker arm protruding from the base web.
 5. Thedust collector for an angle grinder as claimed in claim 3, wherein theat least one spring element has at least one holding bracket, designedto prevent the sealing element from falling axially out of the collectorbody.
 6. The dust collector for an angle grinder as claimed in claim 5,wherein the holding bracket protrudes in the axial direction from thebase web and an axial stop for a holding rail of the sealing element isformed at an other end of the base web, wherein the holding bracket canbe deflected in a radial direction, in relation to the axis of rotation(R) of the grinding wheel, for replacing the sealing element.
 7. Thedust collector for an angle grinder as claimed in claim 6, wherein theaxial stop is formed by a stop web, which extends parallel to the baseweb.
 8. The dust collector for an angle grinder as claimed in claim 5,wherein the holding bracket is designed as a clamping sleeve, which isarranged on a side of a respective spring rocker arm facing away fromthe base web and is designed for clamping a holding rail of the sealingelement.
 9. The dust collector for an angle grinder as claimed in claim1, wherein the at least one spring element is formed in one piece. 10.The dust collector for an angle grinder as claimed in claim 1, whereinthe sealing element comprises brushes and the spring element has aspring stiffness in an axial direction which is less than a stiffness ofthe brushes.
 11. The dust collector for an angle grinder as claimed inclaim 1, wherein a plurality of spring elements are provided along theouter periphery of the collector body.
 12. The dust collector for anangle grinder as claimed in claim 1, wherein the angle grinder has aframe, and the collector body has a central opening, through which adrive spindle, on which the circular grinding wheel is to be attached,can protrude, wherein a groove is formed at the central opening, andtherefore the collector body can be fastened interlocked and thus fixedon the frame.
 13. An angle grinder comprising a dust collector for anangle grinder as claimed in claim 1, wherein the angle grinder has aframe, and collector body is arranged or can be arranged fixed on theframe.
 14. The dust collector of claim 3, wherein the base web is flat.15. The dust collector of claim 2, wherein the spring element has a baseweb via which the at least one spring element is fastened on thecollector body and/or the collector segment.
 16. The dust collector ofclaim 15, wherein the at least one spring element is fastened on thecollector body and/or the collector segment by a pin, a screw, or arivet.
 17. The dust collector of claim 7, wherein the stop web has arecess such that a contact surface between the stop web and the sealingelement is reduced.
 18. The dust collector of claim 9, wherein the atleast one spring element is spring steel.
 19. The dust collector ofclaim 4, wherein the at least one spring rocker arm protrudes from thebase web in an orientation corresponding to the outer periphery of thecollector body.
 20. The dust collector of claim 15, wherein the at leastone spring element has at least one holding bracket designed to preventthe sealing element from falling axially out of the collector bodyand/or the collector segment.